Humidity control

[Riverwart]

Looking for any kind of non-expensive, low-tech tricks to lower the humidity in a 44 gallon grow bucket setup. Using an actual dehumidifier is NOT an option.
After hooking up my ventilation to draw indoor air to an outdoor growing space, I am pleased with the temp, it stays within 1 degree of the indoors, but the humidity seems high. Getting readings of 50-70%. Have placed 2 "eva dry" rechargeable dehumidification gadgets to the bucket but it seems to have little or no impact. My vent intake is 3' of 4" duct pipe with a 200cfm fan set up to passively pull air from inside thru the intake & out the 4" exhaust port.
thanks for any input

[Weed Pharma]

I like to grow in 40-60% conditions-
If you can increase the temps a bit, it will reduce the humidity !

[Riverwart]

Thanks for the feedback. The readings I report come from an empty space. A little concerned that when the grow is in place, the humidity inside could possibly spike even higher. Will try reducing airflow to see if it allow temps to raise a bit from the incoming flow (73-77"ish"). Currently running a difference of 12-17 degrees between inside the can to the temp where the can sits.
Thanks again!

[Campesino]

Yeah, I think your best plan is to keep air-flow high. 70% is high, but I hit it occasionally in my tent. It can be done.
If you reduce airflow it will raise RH faster than temp, so keep it high. If you keep airflow through the space brisk enough, I think you will be able to manage.

[Riverwart]

Thanks campesino!
You know, its funny, turned off the fan for a couple hours earlier this p.m., & when I checked the gauge, the RH was reading 43%inside can.. The outdoor ambient RH outside the can is 81%. The RH from the room where my intake sits(a.c.-cooled room) is 60%. When the airflow is non-existent, those cheezy "eva dry" gadgets seem to have more measurable effect. My guess is the fan is moving air thru the system too fast for the gadgets to do any meaningful dehumidification. From all indications, Im getting signifigant negative pressure inside the can (thank you flex-seal!). Thinking that maybe if I can get the intake air to "stage" a bit before getting pulled thru, those eva dry gadgets might actually help keep the RH down before it gets to the can.
Again, thanks for your input. Its very valued.

[Campesino]

No worries!
Now that you don't have plants, you are just dealing with ambient humidity. Once you get wet media and a transpiring plant in there, most of the humidity will come from that. You can only hope to keep it close to the intake RH (You say 60%), by moving air through quickly. I think you'll be able to manage, but I really doubt the eva dry is going to help.
60% is not ideal, but it can be managed... My tent is 65% right now (lights on!). I hope to get it back down, but it has run high this entire grow. I have good air-flow and haven't had any issues thus far.

[alltatup]

Hi Riverwart, welcome to the forum. I hope you find a solution to the humidity problem, because you sure don't want mildew or bud rot. Put in all that work and end up with rotten bud...

I grow hydroponically too. I had to get a 50-pint dehumidifier and a reservoir chiller because where I live the summer is too hot and humid. Either that or not grow in the summer, which wasn't an option I wanted to consider.

[rizcuny]

I have recently added more CfL’s to my tent, increasing the temperature which then decreased the humidity massively down to 45 from 65. Now as I’m still at seedling I am aiming for 65 humidity so I poured a gallon of water on the grow room floor and it’s shot for 45 to 65 with my temp increase of 90farenheit. As for decreasing humidity u can try and make it hotter in the tent or you can use a container of rock salt with a way to drop out water of the bottom of container, put it in the tent and it should take out the moisture from the air. I know with all my lights off during my 4 hours off period my temp is going to drop to around 70 therefore my humidity is going to increase. I plan on using the rock salt method during lights off when u get to flower (as I need humidity of 45. So let me know what works for you